Fix bd-my64: Pre-push hook blocks instead of exports

The original pre-push hook tried to export DB → JSONL during the push,
then run 'git add', but this doesn't work because:

1. The commit is already created when pre-push runs
2. git add in pre-push stages files for a FUTURE commit
3. The current push sends the old commit with stale JSONL
4. Result: dirty git status after push

Fix:
- Pre-push now CHECKS for uncommitted JSONL changes
- If found, it FAILS the push with clear instructions
- User must commit JSONL before pushing
- This prevents stale JSONL from reaching remote

The pre-commit hook already properly flushes changes, so this
catch-all prevents changes made BETWEEN commit and push.

Amp-Thread-ID: https://ampcode.com/threads/T-39a89553-c301-4d4f-b39f-6df9c403d22b
Co-authored-by: Amp <amp@ampcode.com>

examples/git-hooks/README.md

@@ -1,21 +1,29 @@
 # bd Git Hooks
 
-This directory contains git hooks that integrate bd (beads) with your git workflow, solving the race condition between daemon auto-flush and git commits.
+This directory contains git hooks that integrate bd (beads) with your git workflow, preventing stale JSONL from being pushed to remote.
 
 ## The Problem
 
-When using bd in daemon mode, operations trigger a 5-second debounced auto-flush to JSONL. This creates a race condition:
+Two race conditions can occur:
 
-1. User closes issue via MCP → daemon schedules flush (5 sec delay)
-2. User commits code changes → JSONL appears clean
-3. Daemon flush fires → JSONL modified after commit
-4. Result: dirty working tree showing JSONL changes
+1. **Between operations and commits**: Daemon auto-flush (5s debounce) may fire after commit
+   - User closes issue via MCP → daemon schedules flush (5 sec delay)
+   - User commits code changes → JSONL appears clean
+   - Daemon flush fires → JSONL modified after commit
+   - Result: dirty working tree showing JSONL changes
+
+2. **Between commits and pushes**: Changes made after commit but before push (bd-my64)
+   - User commits → pre-commit hook flushes JSONL
+   - User adds comments or updates issues
+   - User pushes → outdated JSONL is pushed
+   - Result: remote has stale JSONL
 
 ## The Solution
 
-These git hooks ensure bd changes are always synchronized with your commits:
+These git hooks ensure bd changes are always synchronized with your commits and pushes:
 
-- **pre-commit** - Flushes pending bd changes to JSONL before commit
+- **pre-commit** - Flushes pending bd changes to JSONL before commit and stages it
+- **pre-push** - Blocks push if JSONL has uncommitted changes (bd-my64)
 - **post-merge** - Imports updated JSONL after git pull/merge
 
 ## Installation
@@ -37,8 +45,9 @@ This will:
 
 ```bash
 cp examples/git-hooks/pre-commit .git/hooks/pre-commit
+cp examples/git-hooks/pre-push .git/hooks/pre-push
 cp examples/git-hooks/post-merge .git/hooks/post-merge
-chmod +x .git/hooks/pre-commit .git/hooks/post-merge
+chmod +x .git/hooks/pre-commit .git/hooks/pre-push .git/hooks/post-merge
 ```
 
 ## How It Works
@@ -58,16 +67,31 @@ This:
 
 The hook is silent on success, fast (no git operations), and safe (fails commit if flush fails).
 
+### pre-push
+
+Before each push, the hook checks:
+
+```bash
+git diff --quiet .beads/beads.jsonl
+```
+
+This prevents pushing stale JSONL by:
+1. Checking if JSONL has uncommitted changes (working tree or staging)
+2. Failing the push with clear error message if changes exist
+3. Instructing user to commit JSONL before pushing again
+
+This solves bd-my64: changes made between commit and push are caught before reaching remote.
+
 ### post-merge
 
 After a git pull or merge, the hook runs:
 
 ```bash
-bd import -i .beads/issues.jsonl
+bd import -i .beads/beads.jsonl
 ```
 
 This ensures your local database reflects the merged state. The hook:
-- Only runs if `.beads/issues.jsonl` exists
+- Only runs if `.beads/beads.jsonl` exists (also checks `issues.jsonl` for backward compat)
 - Imports any new issues or updates from the merge
 - Warns on failure but doesn't block the merge
 
@@ -92,7 +116,7 @@ This ensures your local database reflects the merged state. The hook:
 Remove the hooks:
 
 ```bash
-rm .git/hooks/pre-commit .git/hooks/post-merge
+rm .git/hooks/pre-commit .git/hooks/pre-push .git/hooks/post-merge
 ```
 
 Your backed-up hooks (if any) are in `.git/hooks/*.backup-*`.